Are Western democracies facing an existential crisis? Around the globe, anger and frustration are fueling what may be another historic challenge to political and party establishments.

Nowhere is this more evident than on the 2016 U.S. presidential campaign trail, where political outsiders are riding a wave of voter discontent. These candidates, with little or no political experience, are often discounted as “unelectable.” But in this election cycle, voters seem more interested in an opportunity to vent than the traditional calculus of electability.

This voter anger surged seven months ago. On June 15, former Florida Gov. Jeb Bush announced his candidacy. At the time, he thought his major challenge was to separate himself from the troubled record of his brother concerning Iraq. But he didn’t have long to savor his status as the establishment favorite. The very next day, Donald Trump entered the race with signature bluster. Although Sens. Ted Cruz and Bernie Sanders were positioned outside their respective Senate establishments and mad as hell at things as usual, it was Trump’s announcement — including his statement that Mexico is sending people that have “lots of problems” to America and he was going to “build a great wall” — that electrified the angry Republican voter, changing the race and possibly American politics for the foreseeable future.

Each time Trump survives or even benefits from a politically incorrect viewpoint, he shifts the course of the Republican race in his direction. His attacks on immigration, John McCain, Megyn Kelly and Muslims (to name a few) have helped him tap into a rage among voters who say they were just waiting for someone to “tell it like it is.”

Democrats, too, have seen the trajectory of their expected presidential campaign shift. Although Hillary Clinton is still the frontrunner, the race is more competitive than expected, and Sanders has passionate support among Obama’s young and liberal constituents who prefer his anti-Wall Street, anti-K Street rhetoric.

America’s political system, where anger is the tone and a lack of experience is a valued characteristic, is not alone in experiencing this seismic tremor. Similar turmoil is visible in Europe as formerly marginalized parties and leaders gain traction. Angry nationalists and populists win by running against the European Union and many of its member states’ establishments, further driven by the immigration crisis.

While frustration with the European establishment shows signs of gaining momentum, a host of polling indicators in the U.S. has been flashing red for a decade. Public satisfaction with Washington at the end of the Bush era fell below 30 percent, nearly matching the president’s final approval rating of 35 percent.

Although Obama started with sky-high approval ratings, his first summer brought the newly formed Tea Party out in force, and Democrats started losing Senate, congressional and gubernatorial elections. Today, they are at the lowest point of influence since World War II. Obama’s approval rating seldom climbs to 50 percent. Only one-quarter of the population believes the country is going in the right direction, and approval of Congress is in the teens.

Periodically, an outsider shakes up America’s dominant parties. Barry Goldwater with the Republicans in 1964 and George McGovern with the Democrats in 1972 took control of their respective parties and proceeded to lose in landslides. This year, the level and length of the turmoil is unprecedented, setting the stage for either party to pick an outsider and potentially suffer a substantial defeat.

Several factors drive the angry rhetoric and radical change here and in European democracies:

• Economic distress. The recession of 2008 produced a crisis of capitalism and divisions in economic classes. Continued sluggish growth and the hollowing out of the middle class have left voters disenchanted with conventional party choices. European voters are rejecting austerity politics directed from central bankers and Brussels bureaucracies and are looking for champions on the fringes.

• Demographic trends. The millennial generation, now pouring into the American electorate, is uninterested in political experience and much interested in change. They are nominally Democrats, but are unattached to the establishment and to old-time institutions. The term “socialism” has no bad connotations.

•Global displacement. A number of racial, ethnic and religious conflicts breaking out on both continents reflect demographic changes. Millions of young people are moving away from insecurity and toward opportunity. They are pouring into the West, creating tension for existing populations and challenges in assimilation.

• National security. With the above environment, each new terrorist act or brutal murder brings calls for greater local security and demands for a more aggressive foreign policy.

It’s not clear whether the anger of voters will energize productive change or threaten democracy, but in 2016, hot rhetoric and various combinations of nationalism, populism and nativism are so far proving very fruitful for the outsider.

Floyd Ciruli is director of the Crossley Center for Public Opinion Research at the University of Denver and writes the political blog The Buzz.

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